Finding the right input bus format throughout the pipeline is hard
so add atomic_get_input_bus_fmts callback and initialize with the
proper input format from list of supported output formats.
This format can be used in pipeline for negotiating bus format between
the DSI-end of this bridge and the other component closer to pipeline
components.
List of Pixel formats are taken from,
AN13573 i.MX 8/RT MIPI DSI/CSI-2, Rev. 0, 21 March 2022
3.7.4 Pixel formats
Table 14. DSI pixel packing formats
v9:
* added MEDIA_BUS_FMT_FIXED
* return MEDIA_BUS_FMT_RGB888_1X24 output_fmt if supported output_fmt
list is unsupported.
* added MEDIA_BUS_FMT_YUYV10_1X20, MEDIA_BUS_FMT_YUYV12_1X24
v8:
* added pixel formats supported by NXP AN13573 i.MX 8/RT MIPI DSI/CSI-2
v7, v6, v5, v4:
* none
v3:
* include media-bus-format.h
v2:
* none
v1:
* new patch
Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Signed-off-by: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/samsung-dsim.c | 69 +++++++++++++++++++++++++++
1 file changed, 69 insertions(+)
diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
index 9203116f1efb..ef0d802d25bf 100644
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -15,6 +15,7 @@
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/irq.h>
+#include <linux/media-bus-format.h>
#include <linux/of_device.h>
#include <linux/phy/phy.h>
@@ -1348,6 +1349,73 @@ static void samsung_dsim_atomic_post_disable(struct drm_bridge *bridge,
pm_runtime_put_sync(dsi->dev);
}
+/*
+ * This pixel output formats list referenced from,
+ * AN13573 i.MX 8/RT MIPI DSI/CSI-2, Rev. 0, 21 March 2022
+ * 3.7.4 Pixel formats
+ * Table 14. DSI pixel packing formats
+ */
+static const u32 samsung_dsim_pixel_output_fmts[] = {
+ MEDIA_BUS_FMT_YUYV10_1X20,
+ MEDIA_BUS_FMT_YUYV12_1X24,
+ MEDIA_BUS_FMT_UYVY8_1X16,
+ MEDIA_BUS_FMT_RGB101010_1X30,
+ MEDIA_BUS_FMT_RGB121212_1X36,
+ MEDIA_BUS_FMT_RGB565_1X16,
+ MEDIA_BUS_FMT_RGB666_1X18,
+ MEDIA_BUS_FMT_RGB888_1X24,
+
+ MEDIA_BUS_FMT_FIXED,
+};
+
+static bool samsung_dsim_pixel_output_fmt_supported(u32 fmt)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(samsung_dsim_pixel_output_fmts); i++) {
+ if (samsung_dsim_pixel_output_fmts[i] == fmt)
+ return true;
+ }
+
+ return false;
+}
+
+static u32 *
+samsung_dsim_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
+ struct drm_bridge_state *bridge_state,
+ struct drm_crtc_state *crtc_state,
+ struct drm_connector_state *conn_state,
+ u32 output_fmt,
+ unsigned int *num_input_fmts)
+{
+ u32 *input_fmts;
+
+ if (!samsung_dsim_pixel_output_fmt_supported(output_fmt))
+ /*
+ * Some bridge/display drivers are still not able to pass the
+ * correct format, so handle those pipelines by falling back
+ * to the default format till the supported formats finalized.
+ */
+ output_fmt = MEDIA_BUS_FMT_RGB888_1X24;
+
+ input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
+ if (!input_fmts)
+ return NULL;
+
+ switch (output_fmt) {
+ case MEDIA_BUS_FMT_FIXED:
+ input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
+ break;
+ default:
+ input_fmts[0] = output_fmt;
+ break;
+ }
+
+ *num_input_fmts = 1;
+
+ return input_fmts;
+}
+
static int samsung_dsim_atomic_check(struct drm_bridge *bridge,
struct drm_bridge_state *bridge_state,
struct drm_crtc_state *crtc_state,
@@ -1396,6 +1464,7 @@ static const struct drm_bridge_funcs samsung_dsim_bridge_funcs = {
.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
.atomic_reset = drm_atomic_helper_bridge_reset,
+ .atomic_get_input_bus_fmts = samsung_dsim_atomic_get_input_bus_fmts,
.atomic_check = samsung_dsim_atomic_check,
.atomic_pre_enable = samsung_dsim_atomic_pre_enable,
.atomic_enable = samsung_dsim_atomic_enable,
--
2.25.1
